bims-medica 2024-06-23 papers

bims-medica

Biomed News

on Metabolism and diet in cancer

Issue of 2024–06–23
eightteen papers selected by
Brett Chrest, East Carolina University

Metabolic adaptation in epithelial ovarian cancer metastasis.
Characterization of β-Hydroxybutyrate as a Cell Autonomous Fuel for Active Excitatory and Inhibitory Neurons.
Key role of glutamine metabolism in persistence of leukemic cells upon exposition to FLT3 tyrosine kinase inhibitors.
Diet predisposes to pancreatic cancer through cellular nutrient sensing pathways.
Spontaneous Tumor Regression and Reversion: Insights and Associations with Reduced Dietary Phosphate.
Label-free fluorescence lifetime imaging for the assessment of cell viability in living tumor fragments.
Exploring the potential of asparagine restriction in solid cancer treatment: recent discoveries, therapeutic implications, and challenges.
Metabolic Profiling of Glioblastoma Stem Cells Reveals Pyruvate Carboxylase as a Critical Survival Factor and Potential Therapeutic Target.
Real-Time Metabolic Magnetic Resonance Spectroscopy of Pancreatic and Colon Cancer Tumor-Xenografts with Parahydrogen Hyperpolarized 1-13C Pyruvate-d3.
Effects of Early and Late Time-Restricted Feeding on Parameters of Metabolic Health: An Explorative Literature Assessment.
Exploration of dietary interventions to treat mitochondrial fatty acid disorders in a mouse model.
Do NPM1 and FLT3-ITD mutations modify prognosis in patients treated with non-intensive regimens?
Glucose Load Following Prolonged Fasting Increases Oxidative Stress-Linked Response in Individuals With Diabetic Complications.
Assessing metabolic rates in zebrafish using a 3D-printed intermittent-flow respirometer and swim tunnel system.
Lactate supports cell-autonomous ECM production to sustain metastatic behavior in prostate cancer.
Discovery of JNJ-74856665: A Novel Isoquinolinone DHODH Inhibitor for the Treatment of AML.
Targeting the sphingolipid rheostat in IDH1 mut glioma alters cholesterol homeostasis and triggers apoptosis via membrane degradation.
µPhos: a scalable and sensitive platform for high-dimensional phosphoproteomics.

Biochim Biophys Acta Mol Basis Dis. 2024 Jun 18. pii: S0925-4439(24)00305-3. [Epub ahead of print]1870(7): 167312

Metabolic adaptation in epithelial ovarian cancer metastasis.

Mallory I Frederick, Mohamed Z Nassef, Matthew J Borrelli, Siyun Kuang, Adrian Buensuceso, Tushar More, Thekla Cordes, Patrick O'Donoghue, Trevor G Shepherd, Karsten Hiller, Ilka U Heinemann.

  Epithelial ovarian cancer (EOC) is highly lethal due to its unique metastatic characteristics. EOC spheroids enter a non-proliferative state, with hypoxic cores and reduced oncogenic signaling, all of which contribute to tumour dormancy during metastasis. We investigated the metabolomic states of EOC cells progressing through the three steps to metastasis. Metabolomes of adherent, spheroid, and re-adherent cells were validated by isotopic metabolic flux analysis and mitochondrial functional assays to identify metabolic pathways that were previously unknown to promote EOC metastasis. Although spheroids were thought to exist in a dormant state, metabolomic analysis revealed an unexpected upregulation of energy production pathways in spheroids, accompanied by increased abundance of tricarboxylic acid (TCA) cycle and electron transport chain proteins. Tracing of 13C-labelled glucose and glutamine showed increased pyruvate carboxylation and decreased glutamine anaplerosis in spheroids. Increased reductive carboxylation suggests spheroids adjust redox homeostasis by shuttling cytosolic NADPH into mitochondria via isocitrate dehydrogenase. Indeed, we observed spheroids have increased respiratory capacity and mitochondrial ATP production. Relative to adherent cells, spheroids reduced serine consumption and metabolism, processes which were reversed upon spheroid re-adherence. The data reveal a distinct metabolism in EOC spheroids that enhances energy production by the mitochondria while maintaining a dormant state with respect to growth and proliferation. The findings advance our understanding of EOC metastasis and identify the TCA cycle and mitochondrional activity as novel targets to disrupt EOC metastasis, providing new approaches to treat advanced disease.

Keywords:  Anaplerosis; Metabolomics; Metastasis; Ovarian cancer; Oxidative phosphorylation; Serine; Spheroid; Tricarboxylic acid (TCA) cycle; electron transport chain

DOI:  https://doi.org/10.1016/j.bbadis.2024.167312
bioRxiv. 2024 Jun 09. pii: 2024.06.08.598077. [Epub ahead of print]

Characterization of β-Hydroxybutyrate as a Cell Autonomous Fuel for Active Excitatory and Inhibitory Neurons.

Kirsten Bredvik, Charmaine Liu, Timothy A Ryan.

The ketogenic diet is an effective treatment for drug-resistant epilepsy, but the therapeutic mechanisms are poorly understood. Although ketones are able to fuel the brain, it is not known whether ketones are directly metabolized by neurons on a time scale sufficiently rapid to fuel the bioenergetic demands of sustained synaptic transmission. Here, we show that nerve terminals can use the ketone β-hydroxybutyrate in a cell- autonomous fashion to support neurotransmission in both excitatory and inhibitory nerve terminals and that this flexibility relies on Ca 2+ dependent upregulation of mitochondrial metabolism. Using a genetically encoded ATP sensor, we show that inhibitory axons fueled by ketones sustain much higher ATP levels under steady state conditions than excitatory axons, but that the kinetics of ATP production following activity are slower when using ketones as fuel compared to lactate/pyruvate for both excitatory and inhibitory neurons.
Significance Statement: The ketogenic diet is a standard treatment for drug resistant epilepsy, but the mechanism of treatment efficacy is largely unknown. Changes to excitatory and inhibitory balance is one hypothesized mechanism. Here, we determine that ATP levels are differentially higher in inhibitory neurons compared to excitatory neurons, suggesting that greater mitochondrial ATP production in inhibitory neurons could be one mechanism mediating therapeutic benefit. Further, our studies of ketone metabolism by synaptic mitochondria should inform management of side effects and risks associated with ketogenic diet treatments. These results provide novel insights that clarify the role of ketones at the cellular level in ketogenic diet treatment for intractable epilepsy and inform the use of ketogenic diets for neurologic and psychiatric conditions more broadly.

DOI: https://doi.org/10.1101/2024.06.08.598077
Exp Hematol. 2024 Jun 13. pii: S0301-472X(24)00112-7. [Epub ahead of print] 104253

Key role of glutamine metabolism in persistence of leukemic cells upon exposition to FLT3 tyrosine kinase inhibitors.

Raeeka Khamari, Claire Degand, Quentin Fovez, Anne Trinh, Axel Chomy, William Laine, Salim Dekiouk, Bart Ghesquiere, Bruno Quesnel, Philippe Marchetti, Salomon Manier, Jérôme Kluza.

  Acute myeloid leukemias are a group of hematological malignancies characterized by a poor prognosis for survival. The discovery of oncogenic mutations in the FLT3 gene has led to the development of tyrosine kinase inhibitors such as Quizartinib. However, achieving complete remission in patients remains challenging because these new TKIs are unable to completely eradicate all leukemic cells. Residual leukemic cells persist during Quizartinib treatment, leading to the rapid emergence of drug-resistant leukemia. Given that mitochondrial oxidative metabolism promotes the survival of leukemic cells after exposure to multiple anticancer drugs, we characterized the metabolism of leukemic cells that persisted during Quizartinib treatment and developed metabolic strategies to eradicate them. In our study, employing biochemical and metabolomics approaches, we confirmed that the survival of leukemic cells treated with FLT3 inhibitors critically depends on maintaining mitochondrial metabolism, specifically through glutamine oxidation. We uncovered a synergistic interaction between the FLT3 inhibitor Quizartinib and L-Asparaginase, operating through anti-metabolic mechanisms. Utilizing various models of persistent leukemia, we demonstrated that leukemic cells resistant to Quizartinib are susceptible to L-Asparaginase. This combined therapeutic strategy shows promise in reducing the development of resistance to FLT3 inhibitors, offering a potential strategy to enhance treatment outcomes.

Keywords:  AML; energy metabolism; glycolysis; leukemia; mitochondria; resistance

DOI:  https://doi.org/10.1016/j.exphem.2024.104253
FEBS Lett. 2024 Jun 17.

Diet predisposes to pancreatic cancer through cellular nutrient sensing pathways.

Roberta Noè, Alessandro Carrer.

  Pancreatic cancer is a lethal disease with limited effective treatments. A deeper understanding of its molecular mechanisms is crucial to reduce incidence and mortality. Epidemiological evidence suggests a link between diet and disease risk, though dietary recommendations for at-risk individuals remain debated. Here, we propose that cell-intrinsic nutrient sensing pathways respond to specific diet-derived cues to facilitate oncogenic transformation of pancreatic epithelial cells. This review explores how diet influences pancreatic cancer predisposition through nutrient sensing and downstream consequences for (pre-)cancer cell biology. We also examine experimental evidence connecting specific food intake to pancreatic cancer progression, highlighting nutrient sensing as a promising target for therapeutic development to mitigate disease risk.

Keywords:  carbohydrates; diet; lipids; nutrient sensing; pancreatic cancer

DOI:  https://doi.org/10.1002/1873-3468.14959
Cancers (Basel). 2024 Jun 03. pii: 2126. [Epub ahead of print]16(11):

Spontaneous Tumor Regression and Reversion: Insights and Associations with Reduced Dietary Phosphate.

Ronald B Brown.

  Tumors that spontaneously shrink from unknown causes in tumor regression, and that return to normal cells in tumor reversion, are phenomena with the potential to contribute new knowledge and novel therapies for cancer patient survival. Tumorigenesis is associated with dysregulated phosphate metabolism and an increased transport of phosphate into tumor cells, potentially mediated by phosphate overload from excessive dietary phosphate intake, a significant problem in Western societies. This paper proposes that reduced dietary phosphate overload and reregulated phosphate metabolism may reverse an imbalance of kinases and phosphatases in cell signaling and cellular proliferation, thereby activating autophagy in tumor regression and reversion. Dietary phosphate can also be reduced by sickness-associated anorexia, fasting-mimicking diets, and other diets low in phosphate, all of which have been associated with tumor regression. Tumor reversion has also been demonstrated by transplanting cancer cells into a healthy microenvironment, plausibly associated with normal cellular phosphate concentrations. Evidence also suggests that the sequestration and containment of excessive phosphate within encapsulated tumors is protective in cancer patients, preventing the release of potentially lethal amounts of phosphate into the general circulation. Reducing dietary phosphate overload has the potential to provide a novel, safe, and effective reversion therapy for cancer patients, and further research is warranted.

Keywords:  autophagy; dietary phosphate overload; dysregulated phosphate metabolism; fasting-mimicking diet; kinases and phosphatases; sickness-associated anorexia; spontaneous tumor regression; tumor encapsulation; tumor microenvironment; tumor reversion

DOI:  https://doi.org/10.3390/cancers16112126
J Biomed Opt. 2024 Jun;29(Suppl 2): S22709

Label-free fluorescence lifetime imaging for the assessment of cell viability in living tumor fragments.

Jason T Smith, Chao J Liu, Jeannine Degnan, Jonathan N Ouellette, Matthew W Conklin, Anna V Kellner, Christina M Scribano, Laura Hrycyniak, Jonathan D Oliner, Chris Zahm, Eric Wait, Kevin W Eliceiri, John Rafter.

   Significance: To enable non-destructive longitudinal assessment of drug agents in intact tumor tissue without the use of disruptive probes, we have designed a label-free method to quantify the health of individual tumor cells in excised tumor tissue using multiphoton fluorescence lifetime imaging microscopy (MP-FLIM).
Aim: Using murine tumor fragments which preserve the native tumor microenvironment, we seek to demonstrate signals generated by the intrinsically fluorescent metabolic co-factors nicotinamide adenine dinucleotide phosphate [NAD(P)H] and flavin adenine dinucleotide (FAD) correlate with irreversible cascades leading to cell death.
Approach: We use MP-FLIM of NAD(P)H and FAD on tissues and confirm viability using standard apoptosis and live/dead (Caspase 3/7 and propidium iodide, respectively) assays.
Results: Through a statistical approach, reproducible shifts in FLIM data, determined through phasor analysis, are shown to correlate with loss of cell viability. With this, we demonstrate that cell death achieved through either apoptosis/necrosis or necroptosis can be discriminated. In addition, specific responses to common chemotherapeutic treatment inducing cell death were detected.
Conclusions: These data demonstrate that MP-FLIM can detect and quantify cell viability without the use of potentially toxic dyes, thus enabling longitudinal multi-day studies assessing the effects of therapeutic agents on tumor fragments.

Keywords:  apoptosis; cancer; cell death; fluorescence lifetime; fluorescence lifetime microscopy; metabolism; multiphoton; necroptosis; nicotinamide adenine dinucleotide phosphate

DOI:  https://doi.org/10.1117/1.JBO.29.S2.S22709
Med Oncol. 2024 Jun 15. 41(7): 176

Exploring the potential of asparagine restriction in solid cancer treatment: recent discoveries, therapeutic implications, and challenges.

Marina Gabriel Fontes, Carolina Silva, William Henry Roldán, Gisele Monteiro.

  Asparagine is a non-essential amino acid crucial for protein biosynthesis and function, and therefore cell maintenance and growth. Furthermore, this amino acid has an important role in regulating several metabolic pathways, such as tricarboxylic acid cycle and the urea cycle. When compared to normal cells, tumor cells typically present a higher demand for asparagine, making it a compelling target for therapy. In this review article, we investigate different facets of asparagine bioavailability intricate role in malignant tumors raised from solid organs. We take a comprehensive look at asparagine synthetase expression and regulation in cancer, including the impact on tumor growth and metastasis. Moreover, we explore asparagine depletion through L-asparaginase as a potential therapeutic method for aggressive solid tumors, approaching different formulations of the enzyme and combinatory therapies. In summary, here we delve into studies about endogenous and exogenous asparagine availability in solid cancers, analyzing therapeutic implications and future challenges.

Keywords:  Amino acid deprivation; Biopharmaceutical; Cancer metabolism; Metastasis

DOI:  https://doi.org/10.1007/s12032-024-02424-3
Neuro Oncol. 2024 Jun 13. pii: noae106. [Epub ahead of print]

Metabolic Profiling of Glioblastoma Stem Cells Reveals Pyruvate Carboxylase as a Critical Survival Factor and Potential Therapeutic Target.

Ophélie Renoult, Mélanie Laurent-Blond, Hala Awada, Lisa Oliver, Noémie Joalland, Mikaël Croyal, François Paris, Catherine Gratas, Claire Pecqueur.

   BACKGROUND: Glioblastoma (GBM) is a highly aggressive tumor with unmet therapeutic needs, which can be explained by extensive intra-tumoral heterogeneity and plasticity. In this study, we aimed to investigate the specific metabolic features of Glioblastoma stem cells (GSC), a rare tumor subpopulation involved in tumor growth and therapy resistance.
METHODS: We conducted comprehensive analyses of primary patient-derived GBM cultures and GSC-enriched cultures of human GBM cell lines using state-of-the-art molecular, metabolic and phenotypic studies.
RESULTS: We showed that GSC-enriched cultures display distinct glycolytic profiles compared with differentiated tumor cells. Further analysis revealed that GSC relies on pyruvate carboxylase activity for survival and self-renewal capacity. Interestingly, inhibition of pyruvate carboxylase led to GSC death, particularly when the glutamine pool was low, and increased differentiation. Finally, while GSC displayed resistance to the chemotherapy drug etoposide, genetic or pharmacological inhibition of pyruvate carboxylase restored etoposide sensitivity in GSC, both in vitro and in orthotopic murine models.
CONCLUSION: Our findings demonstrate the critical role of pyruvate carboxylase in GSC metabolism, survival and escape to etoposide. They also highlight pyruvate carboxylase as a therapeutic target to overcome therapy resistance in GBM.

Keywords:  Cancer stem cells; glioblastoma; metabolic vulnerability; mitochondrial metabolism; pyruvate carboxylation

DOI:  https://doi.org/10.1093/neuonc/noae106
Chemistry. 2024 Jun 18. e202400187

Real-Time Metabolic Magnetic Resonance Spectroscopy of Pancreatic and Colon Cancer Tumor-Xenografts with Parahydrogen Hyperpolarized 1-13C Pyruvate-d3.

Lisa Fries, Theresa Hune, Sonja Sternkopf, Salvatore Mamone, Kim Lucia Schneider, Ramona Schulz-Heddergott, Dorothea Becker, Stefan Glöggler.

  Parahydrogen-induced polarization (PHIP) is an emerging technique to enhance the signal of stable isotope metabolic contrast agents for Magnetic Resonance (MR). The objective of this study is to continue establishing 1-13C-pyruvate-d3, signal-enhanced via PHIP, as a hyperpolarized contrast agent, obtained in seconds, to monitor metabolism in human cancer. Our focus was on human pancreatic and colon tumor xenografts. 1-13C-vinylpyruvate-d6 was hydrogenated using parahydrogen. Thereafter, the polarization of the protons was transferred to 13C. Following a workup procedure, the free hyperpolarized 1-13C-pyruvate-d3 was obtained in clean aqueous solution. After injection into animals bearing either pancreatic or colon cancer xenografts, slice-selective MR spectra were acquired and analyzed to determine rate constants of metabolic conversion into lactate and alanine. 1-13C-pyruvate-d3 proved to follow the increased metabolic rate to lactate and alanine in the tumor xenografts.

Keywords:  NMR; hyperpolarization; parahydrogen

DOI:  https://doi.org/10.1002/chem.202400187
Nutrients. 2024 May 31. pii: 1721. [Epub ahead of print]16(11):

Effects of Early and Late Time-Restricted Feeding on Parameters of Metabolic Health: An Explorative Literature Assessment.

Froso Petridi, Jan M W Geurts, Jean Nyakayiru, Anne Schaafsma, Dedmer Schaafsma, Ruth C R Meex, Cécile M Singh-Povel.

  Chrono-nutrition (meal timing) aligns food consumption with one's circadian rhythm. The first meal (e.g., breakfast) likely promotes synchronization of peripheral circadian clocks, thereby supporting metabolic health. Time-restricted feeding (TRF) has been shown to reduce body weight (BW) and/or improve cardiovascular biomarkers. In this explorative literature assessment, 13 TRF randomized controlled trials (RCTs) were selected from PubMed and Scopus to evaluate the effects of early (eTRF: first meal before 10:30 a.m.) and late TRF (lTRF: first meal after 11:30 a.m.) on parameters of metabolic health. Although distinct variations in study design were evident between reports, TRF consistently decreased energy intake (EI) and BW, and improved insulin resistance as well as systolic blood pressure. eTRF seemed to have a greater beneficial effect than lTRF on insulin resistance (HOMA-IR). Importantly, most studies did not appear to consider chronotype in their evaluation, which may have underestimated TRF effects. TRF intervention may be a promising approach for risk reduction of human metabolic diseases. To conclusively determine benefits of TRF and identify clear differences between eTRF and lTRF, future studies should be longer-term (≥8 weeks) with well-defined (differences in) feeding windows, include participants chronotypically matching the intervention, and compare outcomes to those of control groups without any dietary limitations.

Keywords:  TRE; TRF; chronotype; insulin resistance; metabolic health; overweight; randomized controlled trial; time-restricted feeding; weight loss

DOI:  https://doi.org/10.3390/nu16111721
J Nutr Biochem. 2024 Jun 13. pii: S0955-2863(24)00125-6. [Epub ahead of print] 109692

Exploration of dietary interventions to treat mitochondrial fatty acid disorders in a mouse model.

Kaija J Autio, Hennariikka Koivisto, Werner Schmitz, Anna Puronurmi, Heikki Tanila, Alexander J Kastaniotis.

  Mitochondrial fatty acids synthesis (mtFAS) is a conserved metabolic pathway essential for mitochondrial respiration. The best characterized mtFAS product is the medium-chain fatty acid octanoate (C8) used as a substrate in the synthesis of lipoic acid (LA), a cofactor required by several mitochondrial enzyme complexes. In humans, mutations in the mtFAS component enoyl reductase MECR cause childhood-onset neurodegenerative disorder MEPAN. A complete deletion of Mecr in mice is embryonically lethal, while selective deletion of Mecr in cerebellar Purkinje cells causes neurodegeneration in these cells. A fundamental question in the research of mtFAS deficiency is if the defect is amenable to treatment by supplementation with known mtFAS products. Here we used the Purkinje-cell specific mtFAS deficiency neurodegeneration model mice to study if feeding the mice with a medium-chain triacylglycerol-rich formula supplemented with LA could slow down or prevent the neurodegeneration in Purkinje cell-specific Mecr KO mice. Feeding started at the age of 4 weeks and continued until the age of 9 months. The neurological status on the mice was assessed at the age of 3, 6 and 9 months with behavioral tests and the state of the Purkinje cell deterioration in the cerebellum was studied histologically. We showed that feeding the mice with medium chain triacylglycerols and LA affected fatty acid profiles in the cerebellum and plasma but did not prevent the development of neurodegeneration in these mice. Our results indicate that dietary supplementation with medium chain fatty acids and LA alone is not an efficient way to treat mtFAS disorders.

Keywords:  Mitochondrial fatty acid synthesis; lipoic acid; medium chain fatty acid; mouse model; neurodegeneration

DOI:  https://doi.org/10.1016/j.jnutbio.2024.109692
Ann Hematol. 2024 Jun 17.

Do NPM1 and FLT3-ITD mutations modify prognosis in patients treated with non-intensive regimens?

PETHEMA group

  FLT3-ITD and NPM1 mutations are key to defining the genetic risk profile of acute myeloid leukemia (AML). We aimed to assess the prognostic features of the FLT3-ITD and NPM1 mutations in old and/or unfit individuals with AML treated with non-intensive therapies in the era before azacitidine-venetoclax approbation. The results of various non-intensive regimens were also compared. We conducted a retrospective analysis that included patients treated with different non-intensive regimens, between 2007 and 2020 from PETHEMA AML registry. We compiled 707 patients with a median age of 74 years and median follow-up time of 37.7 months. FLT3-ITD patients (N = 98) showed a non-significant difference in overall survival (OS) compared to FLT3-ITD negative-patients (N = 608) (P = 0.17, median OS was 5 vs 7.3 months respectively). NPM1-mutated patients (N = 144) also showed a non-significant difference with NPM1 wild type (N = 519) patients (P = 0.25, median OS 7.2 vs 6.8 respectively). In the Cox regression analysis neither NPM1 nor FLT3-ITD nor age were significant prognostic variables for OS prediction. Abnormal karyotype and a high leukocyte count showed a statistically significant deleterious effect. Azacitidine also showed better survival compared to FLUGA (low dose cytarabine plus fludarabine). NPM1 and FLT3-ITD seem to lack prognostic value in older/unfit AML patients treated with non-intensive regimens other than azacitidine-venetoclax combination.

Keywords:  Acute myeloid leukemia; Elderly; Fms-like tyrosine kinase 3 (FLT3) mutation; Hypomethylating; Nucleophosmin 1 (NPM1) mutation; PETHEMA; Treatment

DOI:  https://doi.org/10.1007/s00277-024-05840-7
Diabetes Care. 2024 Jun 21. pii: dc240209. [Epub ahead of print]

Glucose Load Following Prolonged Fasting Increases Oxidative Stress-Linked Response in Individuals With Diabetic Complications.

Ekaterina von Rauchhaupt, Claus Rodemer, Elisabeth Kliemank, Ruben Bulkescher, Marta Campos, Stefan Kopf, Thomas Fleming, Stephan Herzig, Peter P Nawroth, Julia Szendroedi, Johanna Zemva, Alba Sulaj.

OBJECTIVE: Prolonged catabolic states in type 2 diabetes (T2D), exacerbated by excess substrate flux and hyperglycemia, can challenge metabolic flexibility and antioxidative capacity. We investigated cellular responses to glucose load after prolonged fasting in T2D.
RESEARCH DESIGN AND METHODS: Glucose-tolerant individuals (CON, n = 10), T2D individuals with (T2D+, n = 10) and without diabetes complications (T2D-, n = 10) underwent oral glucose tolerance test before and after a 5-day fasting-mimicking diet. Peripheral blood mononuclear cells' (PBMC) resistance to ex vivo dicarbonyl methylglyoxal (MG) exposure after glucose load was assessed. Markers of dicarbonyl detoxification, oxidative stress, and mitochondrial biogenesis were analyzed by quantitative PCR, with mitochondrial complex protein expression assessed by western blotting.
RESULTS: T2D+ exhibited decreased PBMC resistance against MG, while T2D- resistance remained unchanged, and CON improved postglucose load and fasting (-19.0% vs.-1.7% vs. 12.6%; all P = 0.017). T2D+ showed increased expression in dicarbonyl detoxification (mRNA glyoxalase-1, all P = 0.039), oxidative stress (mRNA glutathione-disulfide-reductase, all P = 0.006), and mitochondrial complex V protein (all P = 0.004) compared with T2D- and CON postglucose load and fasting. Citrate synthase activity remained unchanged, indicating no change in mitochondrial number. Mitochondrial biogenesis increased in T2D- compared with CON postglucose load and fasting (mRNA HspA9, P = 0.032). T2D-, compared with CON, exhibited increased oxidative stress postfasting, but not postglucose load, with increased mRNA expression in antioxidant defenses (mRNA forkhead box O4, P = 0.036, and glutathione-peroxidase-2, P = 0.034), and compared with T2D+ (glutathione-peroxidase-2, P = 0.04).
CONCLUSIONS: These findings suggest increased susceptibility to glucose-induced oxidative stress in individuals with diabetes complications after prolonged fasting and might help in diet interventions for diabetes management.

DOI: https://doi.org/10.2337/dc24-0209
Biol Open. 2024 Jun 15. pii: bio060375. [Epub ahead of print]13(6):

Assessing metabolic rates in zebrafish using a 3D-printed intermittent-flow respirometer and swim tunnel system.

Rasmus Hejlesen, Freja Burkarl Scheffler, Clara Garfiel Byrge, Kasper Kjær-Sørensen, Claus Oxvig, Angela Fago, Hans Malte.

  Zebrafish have become a widely used vertebrate model in physiology and reliable measures of their metabolic rate are needed. We have developed a 3D-printed respirometer and swim tunnel system and used it for obtaining accurate measurement of standard metabolic rate (SMR) and maximal, aerobic metabolic rate (MMR) in zebrafish under rest and maximal exercise, respectively. We compared a slow (stepwise) protocol to a fast (continuous) protocol for determining MMR. The fast protocol yielded slightly (but not significantly) higher oxygen consumption rates than the slow protocol and the data, in contrast to the slow protocol, followed a normal distribution. These findings point to the fast protocol as a fast and reliable method for obtaining accurate values of MMR in zebrafish. We make the 3D drawings for printing the system available to researchers, to help streamline the field of metabolic research in zebrafish and other smaller fish species.

Keywords:  Aerobic scope; Fish; Maximal metabolic rate; Respirometer; Respirometry; Standard metabolic rate

DOI:  https://doi.org/10.1242/bio.060375
EMBO Rep. 2024 Jun 21.

Lactate supports cell-autonomous ECM production to sustain metastatic behavior in prostate cancer.

Luigi Ippolito, Assia Duatti, Marta Iozzo, Giuseppina Comito, Elisa Pardella, Nicla Lorito, Marina Bacci, Erica Pranzini, Alice Santi, Giada Sandrini, Carlo V Catapano, Sergio Serni, Pietro Spatafora, Andrea Morandi, Elisa Giannoni, Paola Chiarugi.

  Extracellular matrix (ECM) is a major component of the tumor environment, promoting the establishment of a pro-invasive behavior. Such environment is supported by both tumor- and stromal-derived metabolites, particularly lactate. In prostate cancer (PCa), cancer-associated fibroblasts (CAFs) are major contributors of secreted lactate, able to impact on metabolic and transcriptional regulation in cancer cells. Here, we describe a mechanism by which CAF-secreted lactate promotes in PCa cells the expression of genes coding for the collagen family. Lactate-exploiting PCa cells rely on increased α-ketoglutarate (α-KG) which activates the α-KG-dependent collagen prolyl-4-hydroxylase (P4HA1) to support collagen hydroxylation. De novo synthetized collagen plays a signaling role by activating discoidin domain receptor 1 (DDR1), supporting stem-like and invasive features of PCa cells. Inhibition of lactate-induced collagen hydroxylation and DDR1 activation reduces the metastatic colonization of PCa cells. Overall, these results provide a new understanding of the link between collagen remodeling/signaling and the nutrient environment exploited by PCa.

Keywords:  CAFs; Collagen Hydroxylation; Collagen Signaling; Lactate Metabolism

DOI:  https://doi.org/10.1038/s44319-024-00180-z
J Med Chem. 2024 Jun 18.

Discovery of JNJ-74856665: A Novel Isoquinolinone DHODH Inhibitor for the Treatment of AML.

Lindsey G DeRatt, Zhuming Zhang, Christine Pietsch, Justin S Cisar, Xiaochun Zhang, Weixue Wang, Alexandra Tanner, Rosalie Matico, Paul Shaffer, Edgar Jacoby, Faraz Kazmi, Neetu Shukla, Tammy L Bush, Aaron Patrick, Ulrike Philippar, Ricardo Attar, James P Edwards, Scott D Kuduk.

Acute myelogenous leukemia (AML), a heterogeneous disease of the blood and bone marrow, is characterized by the inability of myeloblasts to differentiate into mature cell types. Dihydroorotate dehydrogenase (DHODH) is an enzyme well-known in the pyrimidine biosynthesis pathway and preclinical findings demonstrated that DHODH is a metabolic vulnerability in AML as inhibitors can induce differentiation across multiple AML subtypes. As a result of virtual screening and structure-based drug design approaches, a novel series of isoquinolinone DHODH inhibitors was identified. Further lead optimization afforded JNJ-74856665 as an orally bioavailable, potent, and selective DHODH inhibitor with favorable physicochemical properties selected for clinical development in patients with AML and myelodysplastic syndromes (MDS).

DOI: https://doi.org/10.1021/acs.jmedchem.4c00809
bioRxiv. 2024 Apr 27. pii: 2024.04.26.591321. [Epub ahead of print]

Targeting the sphingolipid rheostat in IDH1 mut glioma alters cholesterol homeostasis and triggers apoptosis via membrane degradation.

Tyrone Dowdy, Helena Muley Vilamu, Adrian Lita, Aiguo Li, Tomohiro Yamasaki, Lumin Zhang, Raj Chari, Hua Song, Meili Zhang, Wei Zhang, Nicole Briceno, Dionne Davis, Mark R Gilbert, Mioara Larion.

The cross-regulation of metabolism and trafficking is not well understood for the vital sphingolipids and cholesterol constituents of cellular compartments. While reports are starting to surface on how sphingolipids like sphingomyelin (SM) dysregulate cholesterol levels in different cellular compartments (Jiang et al., 2022), limited research is available on the mechanisms driving the relationship between sphingolipids and cholesterol homeostasis, or its biological implications. Previously, we have identified sphingolipid metabolism as a unique vulnerability for IDH1 mut gliomas via a rational drug design. Herein, we show how modulating sphingolipid levels affects cholesterol homeostasis in brain tumors. However, we unexpectedly discovered for the first time that C17 sphingosine and NDMS addition to cancer cells alters cholesterol homeostasis by impacting its cellular synthesis, uptake, and efflux leading to a net decrease in cholesterol levels and inducing apoptosis. Our results reflect a reverse correlation between the levels of sphingosines, NDMS, and unesterified, free cholesterol in the cells. We show that increasing sphingosine and NDMS (a sphingosine analog) levels alter not only the trafficking of cholesterol between membranes but also the efflux and synthesis of cholesterol. We also demonstrate that despite the effort to remove free cholesterol by ABCA1-mediated efflux or by suppressing machinery for the influx (LDLR) and biosynthetic pathway (HMGCR), apoptosis is inevitable for IDH1 mut glioma cells. This is the first study that shows how altering sphingosine levels directly affects cholesterol homeostasis in cancer cells and can be used to manipulate this relationship to induce apoptosis in IDH1 mut gliomas.

DOI: https://doi.org/10.1101/2024.04.26.591321
Mol Syst Biol. 2024 Jun 21.

µPhos: a scalable and sensitive platform for high-dimensional phosphoproteomics.

Denys Oliinyk, Andreas Will, Felix R Schneidmadel, Maximilian Böhme, Jenny Rinke, Andreas Hochhaus, Thomas Ernst, Nina Hahn, Christian Geis, Markus Lubeck, Oliver Raether, Sean J Humphrey, Florian Meier.

  Mass spectrometry has revolutionized cell signaling research by vastly simplifying the analysis of many thousands of phosphorylation sites in the human proteome. Defining the cellular response to perturbations is crucial for further illuminating the functionality of the phosphoproteome. Here we describe µPhos ('microPhos'), an accessible phosphoproteomics platform that permits phosphopeptide enrichment from 96-well cell culture and small tissue amounts in <8 h total processing time. By greatly minimizing transfer steps and liquid volumes, we demonstrate increased sensitivity, >90% selectivity, and excellent quantitative reproducibility. Employing highly sensitive trapped ion mobility mass spectrometry, we quantify ~17,000 Class I phosphosites in a human cancer cell line using 20 µg starting material, and confidently localize ~6200 phosphosites from 1 µg. This depth covers key signaling pathways, rendering sample-limited applications and perturbation experiments with hundreds of samples viable. We employ µPhos to study drug- and time-dependent response signatures in a leukemia cell line, and by quantifying 30,000 Class I phosphosites in the mouse brain we reveal distinct spatial kinase activities in subregions of the hippocampal formation.

Keywords:  Drug Response; Mass Spectrometry; Phosphoproteomics; Sample Preparation; Signaling

DOI:  https://doi.org/10.1038/s44320-024-00050-9